The invention relates to a transportable apparatus for taking samples for microbiological, particularly bacteriological tests from surfaces by means of a rinsing liquid atomized by means of a compressed gas, preferably air using a compressed gas supply connection, a rinsing liquid supply connection, an atomizer and a nozzle which can be placed on the surface to be tested, into which can be introduced the compressed gas and the atomized rinsing liquid and which has a drainage line for removing the mixture of compressed gas, rinsing liquid and rinsed off particles and which is connectable by means of a collecting pipe to a collecting tank for the mixture constituted by the rinsing liquid and the rinsed off particles.
Nowadays very high demands are made regarding the hygienic aspects of the activities of manufacturers, processors and traders in foodstuffs and breeders, importers and traders in animals in order to prevent illnesses to both humans and animals, as well as the development of infectious diseases. It is up to food chemists, microbiologists and veterinary surgeons to ensure that the corresponding regulations are adhered to and the fulfilment of this task imposes that the greatest care be taken by their assistants, which is time-consuming and costly, so that it is generally only carried out on a spot check basis. To ensure that incorrect results are not obtained greatest care must be taken during sampling. This applies not only in cases where it is a question of testing materials from which samples can be taken, e.g. with foods, but also in cases where it is a question of investigating the surfaces of objects, e.g. the walls of a dairy or the skin of a chicken, where it is generally difficult to take samples. In order to obtain comparable values it would be advantageous if a standard surface, i.e. a surface area of given size could always be used as a basis. Thus, an apparatus of the above-defined type has already been developed and was described on pp 407 ff of the CANADIAN JOURNAL OF MICROBIOLOGY in 1965. However, this apparatus involves a considerable equipment expenditure and has disadvantages, which have hitherto been prejudicial to its use in practice. A main disadvantage of this apparatus it that its construction leads to a particularly unsatisfactory action, which can be attributed to the fact that only a small part of the atomized rinsing liquid can act on the surface being tested, while the remainder of the said liquid is prevented from doing so by a pressure cushion, which has built up in the nozzles just after the start of operations. This pressure cushion deflects a large part of the atomized rinsing liquid in unused form into the collecting tank, without coming into contact with the surface under investigation. Another disadvantage of this apparatus is that, due to the construction, it can only be used for sampling on vertical surfaces, i.e. cannot be universally used.